diff --git a/actionpack/lib/sprockets/helpers/rails_helper.rb b/actionpack/lib/sprockets/helpers/rails_helper.rb
index fe822b338e883..1e0e9bef777cb 100644
--- a/actionpack/lib/sprockets/helpers/rails_helper.rb
+++ b/actionpack/lib/sprockets/helpers/rails_helper.rb
@@ -114,7 +114,7 @@ def asset_for(source, ext)
         end
 
         def digest_for(logical_path)
-          if asset_digests && (digest = asset_digests[logical_path])
+          if digest_assets && asset_digests && (digest = asset_digests[logical_path])
             return digest
           end
 
diff --git a/actionpack/test/template/sprockets_helper_test.rb b/actionpack/test/template/sprockets_helper_test.rb
index a44a16750f9a4..71768f4f5fa26 100644
--- a/actionpack/test/template/sprockets_helper_test.rb
+++ b/actionpack/test/template/sprockets_helper_test.rb
@@ -262,4 +262,12 @@ def url_for(*args)
 
     assert_not_equal prod_path, dev_path
   end
+
+  test "precedence of `config.digest = false` over manifest.yml asset digests" do
+    Rails.application.config.assets.digests = {'logo.png' => 'logo-d1g3st.png'}
+    @config.assets.digest = false
+
+    assert_match %r{/assets/logo.png},
+      asset_path("logo.png")
+  end
 end